View full sizeSolarWorld employs 775 workers at its factory and U.S. headquarters in Hillsboro.

When will sustainability become sustainable? It's an important economic question for a state such as Oregon that has declared green industries to be a prime target of job-creation efforts.

Even some who champion a green-hued economic development strategy acknowledge that many sustainability-themed businesses struggle to survive with government help, much less without it. A couple of news developments this week involving companies with a heavy Northwest presence illustrate the ongoing tension between doing what's best for the environment and making a profit.

Shares of SolarWorld, the German company with a factory in Hillsboro, plunged Friday on the Frankfurt Stock Exchange after company officials warned of a looming debt restructuring. A day earlier in Bellevue, Wash., a representative of the free-market National Center for Public Policy Research complained at the Costco annual meeting about the membership retailer's sustainability efforts. The practices, charged Justin Danhof, threaten to lower the return on shareholders' investments and increase consumer costs.

SolarWorld and Costco operate in very different industries, have contrasting financial conditions and face mostly dissimilar issues. But they essentially are caught in the same debate: How do businesses balance sustainability and profitability? And do the two goals have to be mutually exclusive?

First, it should be noted that it's hard to measure how much consumer decisions influence the environment. The solar panel that helps reduce carbon emissions might have been made in a coal-fueled Chinese factory, for example. "It's almost impossible for (consumers) to really tease out marginal greenhouse gases," said Portland economist Joe Cortright, who often writes on sustainability and the economy.

For the foreseeable future, it will require a mix of government policy and consumer demand to drive growth of green industries. But these businesses eventually must stand on their own.

Cortright and SolarWorld spokesman Ben Santarris agree that more consistent government policies -- rather than ones that change with each budget cycle -- would help. Cortright also points out that ending or reducing subsidies for carbon fuels would have as much, or more, effect as subsidizing green energy.

What's the short-term takeaway for Oregon? The state is mostly on the right path in seeking to become a leader in green industry and sustainable business practices. But it will require patience and disciplined decision-making, focused on creating a positive environment for all businesses, for the strategy to work.

Meanwhile, neither SolarWorld nor Costco is backing down from its commitments.

SolarWorld last summer announced intentions to invest about $27 million in Hillsboro, mostly for new and upgraded equipment. The company is well along in those efforts, Santarris said, and now expects investments to total $33 million when completed. Thursday wasn't the first time Costco has heard shareholder complaints on a variety of subjects, and it has a record of both sticking to its principles and growing.